An air-cooled refrigerator is generally provided with an air channel, and a cooling compartment for placing an evaporator. Cooling air in the cooling compartment is delivered to each storage compartment by a fan via the air channel. The temperature of the storage compartment is adjusted by controlling the flow rate of the cooling air delivered to the storage compartment.
In order to adjust the flow rate of the cooling air, an electric air door is usually disposed in the air channel. The electric air door is accurate in adjustment and high in controllability, but relatively high in cost, complicated in structure and cumbersome in control, and consumes a certain amount of electrical energy during use.